Replaceable vehicle lamp unit



Sep. 7, 1954 M HOL-fz 2,588,688

REPLACEABLE VEHICLE LAMP UNIT Filed July 22. 1949 3 Sheets-Sheet 1 Sept 7, i954 l.. M. HoLTz REPLACEABLE VEHICLE LAMP UNIT 3 Sheets-Sheet 2 Filed July 22. 1949 FIEL-4.

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/////////ff////w// Sept. 7, 1954 M HQLTZ 2,688,688

REPLACEIABLEJ VEHICLE LAMP UNIT Filed July 22, 1949 3 Sheets-Sheet 3 Patented Sept. 7, 1954 UNITED@ STATES PATENT OFFICE REPLACEABLE VEHICLE LAMP UNIT Louis M. Holtz, Chicago, Ill.

Application July 22, 1949, Serial No. 106;145-

(Cl. 24U-7.1)

2 Claims.

1 This invention relates to vehiclelights and in particular to a structure which provides a selfcontained, easily replaceable lamp unittogether with cooperating means fory mountingr the samev on the body of a vehicle.

The invention is particularly applicable to trical contact between the lamp and the source of power associated with the support.

.Another object of this invention is to provide a combined support and ContactA means of the character described which permits both the elec-` trical and mechanical connection to be established or to be broken by a single movementof the lamp unit.

It is a further object to provide a combined support and contact means Which operates by a wedging action, thereby providing good electrical contact even though the contact members are 'lo. cated in a position wherein they may be exposed to grease and dirt.

A still further object is to provide a tail light, a clearance light or the like, which is in the form of a replaceable unit which includes the lamp bulb and the housing therefor. Thus, when the bulb burns out, the unit as a Whole may be replaced and a fresh unit readily inserted without the necessity of having to remove the housing and replace the lamp bulb.

Trucks and trailers are required to carry clearance lights at the rear of the body, as well as the usual tail light. The clearance lightsk are. generally mounted in a row of three, although sometimes there are more. Due to vibration and the fact that a given truck is oftentimes in use for almost twenty-four hours a day, bulb failure occurs much more frequently than it does in the usual passenger car. Also the factthat there are at least four of these small wattage bulbs on each truck, the probability that at least one bulb will fail duringI a given run is reasonably great. Therefore, the truck drivers have to carry spare bulbs and the installation of a given bulb con-r sumes an appreciable amount of time due to the necessity of removing the lamp housing in order to replace the bulb. Furthermore, the means by which the lamp housing is attached to the body frequently become coated with dirt or grease which renders` theA operation off replacement of:

the bulb more time-consuming.

According to the vpresent invention, the truckdriver carries a stock of fresh replaceable units,

and the operation of replacing can be accomf.

plished in considerably less Ytime than one minute.

since only a single sliding movement is` required for effecting` both the electr-ical and mechanical;

contact.

Still-another` object is to provide a replaceable light unit ofA few parts which lends itself readily` to low` cos-t mass` production.

Other` objects; features a-ndadvantagesv will bccomevapparent as the description proceeds.

With reference now to the drawings invw-hich,

like-reference numerals designate likeparts:

Fig. l is an elevation of ay preferred embodiment` of my invention;

Fig. 2 isr a vertical section taken alongl line 2 2 of Figi;

Fig. 3 is a horizontalvsection taken along linef Figa is an elevation ofthe mounting plate.;

is arear-eievation of the lampunit;- Fig. 6 is an enlarged section taken` along line 6 6 ofFig. 3;

Fig. 7 isan endview of the housing shown inl Fig.. 5.

Fig. 8 is anelevation of a modified form of my;

along line 9-9 of Fig. 8;

Fig. 10 is. anV endv view ofA Fig. 8; and;

Fig. l1. is anenlarged section taken along line wall portion ilv of. a'vehicle body or some other A mounting platesuitable supporting means. i?. is securedto-the wall portion iliiby means-of screws I3, Si] and 32 as showngin Figs. 3 and-6.

Wall

.vallswill also be transparent.

A lamp socket il is suitably mountedon the base plate i4 and carries a lamp i8; The transf parentwall iii may be shapedtoform a. bullseye iB or other refracting meansfwhich are cus.-y A tomarny employed ing clearancelights and tailY 3 lights, the bulls eye being located opposite the lamp bulb I8.

Disposed on the mounting plate I2 are two elongate contact members, hereinafter sometimes referred to as mounting contacts 20 and 2|. These are secured to the mounting plate I2 by means of screws 22, as shown in Fig. 6. A pair of somewhat similar elongate contact members, hereinafter sometimes referred to as unit contacts 23 and 24, are secured to the base plate I4 by means of screws 25 as shown in Figs. 3, 5 and 6.. The mounting contacts 20 and 2| extend in the same general direction as do the unit contacts 23 and 24, in order that sliding movement between the two pairs may be effected.

The unit contacts 23 and 24 are provided with oppositely disposed edge portions 26 which are offset from the plane of the bottom surface of the base member, or they may otherwise be shaped so as to provide portions which may be slidably engaged by the mounting contacts 20 and 2|, in interlocking relationship. The mounting contacts are spaced closer to each other than are the unit contacts, and are also provided with oppositely disposed edge portions 26 which bear against the edge portions of the unit contacts and serve to establish electrical Contact between the two. In this particular embodiment, the unit contacts are insulated from each other so that the cooperating contact members of each pair, 20, 24 and 2| and 23, respectively, may be utilized to establish electrical connection with both terminals of the lamp bulb and the power source. Where a metal base plate is used, and the unit contacts are not insulated from each other, the construction herein shown may be utilized to establish connection between one terminal of the lamp bulb and the power source, other means being provided to establish connection between the other terminal and the power source as will be pointed out hereinafter.

As shown in the drawings, the contact members are disposed not exactly parallel -to each other, but preferably at a slight angle to each other in order to obtain a wedging action in a direction parallel to the plane of the base and the mounting plates. However, they may be otherwise shaped to provide a wedging action in a plane perpendicular to the plane of the base and mounting plates. This wedging action provides a good electrical contact even though the contact members might be coated with dirt or grease.

The housing I5 is formed with an inwardly directed ange 21 which extends around three of the four walls thereof and which forms a seat for the base plate I4. The base plate I4 is secured in place by means of a screw 28 which passes through the fourth wall of the housing and takes into the edge of the base plate.

The base of the socket I1 is secured to the base plate I4 by means of one of the screws 25 as shown in Figs. 2 and 3, thereby providing electrical connection between one terminal of the lamp bulb I8 and the unit contact 23. A conductor 29 provides an electrical connection between the other terminal of the lamp bulb I8 and the unit contact 24, the ends of the conductor 29 being soldered to the lamp terminal and to one of the screws 25 respectively. rlhus, the lamp bulb I8 is electrically connected across the two unit contacts 23 and 24.

Mounting contact 20 is connected to mounting screw 30 by means of a conducting strip 3|, as shown in Fig. 4. Similarly mounting contact 2| is connected to mounting screw 32 by means of a conductor strip 33. The mounting screws 3U and 32 preferably extend through bushings 34 provided in the wall portion II, and serve as means to which an external circuit may be connected. The external circuit may include one or more conductors 35 as shown in Fig. 3 and a source of power, such as a battery, not shown herein. Alternatively, one of the mounting screws 30 or 32 may be grounded to the wall portion II provided that the latter is steel, and the circuit completed by the grounding of one of the battery terminals.

A latch 36 is provided to lock the lamp unit against sliding movement in the event that it is not wedged into position with suicient force. As shown in Fig. 4, one end of the resilient strip from which the latch 36 is formed is disposed between the mounting plate I2 and the wall portion II and is held in place by the screw I3. The underside of the mounting plate is cut away at 31 to permit resilient movement of the latch in a direction perpendicular to the plane of the wall portion I I. The outer end of the latch engages a notch 38 formed in the flange 21 of the housing I5. The outer end of the latch 36 is bent up to provide a button 39. To remove the lamp unit, the button 39 is depressed which frees the lamp unit and permits it to be slid to the left and removed from engagement with the mounting plate I2.

The strips can be very rmly secured to the plates, thereby providing a combined electrical and mechanical connection which is capable of supporting a comparatively heavy load.

In the above described embodiment it is the outer edges of the mounting contacts which cooperate with the inner edges of the unit contacts. However, this arrangement can be reversed by placing the unit contacts close to each other and having them embraced by the mounting contacts.

Another embodiment of my invention is shown in Figs. 8 to 11 in which the interlocking contact members serve to establish electrical connection between just one side of the lamp bulb and the power source, separate means being provided to connect the other side of the lamp bulb to the power source. Also, a somewhat different arrangement of interlocking contact members is shown, the wedging action taking place in a direction which is perpendicular to the plane of the mounting and base plates.

In this embodiment, the lamp unit is designated by the reference numberal 40 and the mounting plate by the reference numeral 4|. The mounting plate in this instance is made from sheet metal and may be secured to the wall of a truck by one or more mounting screws 42. The lamp unit 40 comprises a metal base plate 43 to which a transparent housing 44 is suitably secured by means of screws 49. The metal base plate 43 is provided with an upstanding rim 45 which is provided with outwardly extending flanges 46, which correspond to the unit contacts of the previously described embodiment. The housing 44 seats itself within the rim 45 so as to reduce the lateral strain on the screws 49.

The metal mounting plate 4| is similarly provided with a rim 41 having inwardly directed anges 48 which overhang the flanges 46 and cooperate therewith to establish both mechanical and electrical connection. The flanges 48 correspond to the mounting contacts of the previously described embodiment.

The mounting plate is also provided with longitudinal ridges 59 which may be in the form of stamped corrugations as shown in Fig. 10. These ridges have sloping end portions 5i. The cooperation between the iianges 45 and 48 and the ridges 50 provides a wedging action in a direction perpendiuclar to the plane of the plates 4| and 43, with the result that good electrical contact is provided. The sloping portions 5i serve to facilitate the wedging action, and the contact between the ridges 50 and the undersurface of the base plate d3 provides additional electrical connection between these two metallic members.

As shown in Fig. 11 the base plate 43 is stamped to provide an aperture and flange 52. A cup 53 is pressed into the flanged aperture and a rubber fer-rule 54 is suitably mounted within the cup. The rubber ferrule is provided with a flange 55 which seats against the bottom of the cup and which serves as a diaphragm to provide a resilient mounting for a terminal button 56 which is suitably mounted within the rubber ferrule. Oppositely disposed from the terminal button 56 is a cooperating terminal button 5l which is mounted in a rubber bushing 58, the latter passing through and being secured in the metal mounting plate 4l.

A lamp bulb 59 is suitably mounted on the base plate 43 by means of a socket 50. The latter includes a bracket 6i which supports a cup 62 in which is disposed a rubber ferrule 63 similar in shape and operation to the rubber ferrule 54. A conductor 64 provides electrical connection between the terminal button 55 and a similar terminal button mounted in ferrule 53 for engaging one of the terminals of the lamp bulbs 59.

In operation, it will be observed that the rim 41 is cut away at the right hand portion of the mounting plate 4I as viewed in Fig. 9 so as to permit sliding longitudinal movement of the lamp unit with respect to the mounting plate. As the lamp unit is brought into operative position in which the terminal buttons 56 and 51 are engaged with each other, one or more detents 65 formed in the base plate 43 drop into notches 56 formed in the ridges 50, thereby serving to lock the parts in their operative position. The resilient mounting of the terminal buttons 56 and 5l and particularly the former, causes good electrical contact between the two. It will be observed that the terminal buttons are rounded to facilitate movement of the lamp unit into operative position.

It will be understood that various modications and changes in the embodiments of my invention described and illustrated herein may be made without departing from the spirit of my invention as defined in the appended claims.

I claim:

1. A vehicle light comprising a lamp unit and a mounting plate therefor, said lamp unit comprising a base plate, a lamp bulb mounted thereon, and a transparent housing secured to said base plate and cooperating with said base plate to completely enclose said lamp bulb, said base plate being provided with a pair of oppositely disposed substantially parallel edge portions, and said mounting plate being provided with a cooperating pair of inwardly directed marginal portions overhanging said exposed edge portions so as to interlock therewith, and permitting a straight line sliding engagement whereby said lamp unit may be slidably secured to said mounting plate, said mounting plate being provided with a ridge disposed between said inwardly directed marginal portions and being substantially parallel thereto, said ridge having a sloping portion and having a second portion extending into contact with said base plate and urging the exposed edge portion of said base plate into electrical Contact with said inwardly directed marginal portions of said mounting plate, said sloping portions providing a wedging action in a direction perpendicular to the plane of said mounting plate so as to facilitate the insertion of said exposed edge portions beneath the inwardly directed portions of said mounting plate preparatory to sliding the parts into operative engagement, and means for providing an electrical circuit between said lamp bulb and a power source, said means including said exposed edge portions and said inwardly directed marginal portions.

2. A Vehicle light comprising a replaceable lamp unit and a mounting plate therefor, said lamp unit comprising a substantially rectangular base plate, a lamp bulb mounted thereon with its axis substantially parallel to the plane of said base plate, and a transparent housing secured to said base plate to completely enclose said lamp bulb, said base plate being provided with a pair of oppositely disposed substantially parallel edge portions of a length substantially equal to the length of said base, and said mounting plate being provided with a cooperating pair of inwardly directed marginal portions overhanging said exposed edge portions so as to interlock therewith, and permitting a straight line sliding engagement in a direction parallel to the plane in which said lamp bulb axis is oriented whereby said lamp unit may be slidably secured to said mounting plate, and cooperative means carried by said base plate and said mounting plate for establishing an electrical connection with said lamp bulb when said lamp unit is slid into its operative position.

References Cited in the file of this patent UNITED 4STATES PATENTS Number Name Date Re. 16,254 Leech et al Jan. 19, 1926 1,918,803 Floraday July 18, 1933 2,019,347 Hovey Oct. 29, 1935 2,069,239 Fraser Feb. 3, 1937 2,076,020 Fraser Apr. 6, 1937 2,093,806 Dover Sept. 21, 1937 2,195,189 Sauer Mar. 26, 1940 2,196,313 Laursen Apr. 9, 1940 2,228,333 Abbott Jan. 14, 1941 2,230,521 Bolser Feb. 4, 1941 2,296,369 Richmond Sept. 22, 1942 

